Attorney Jeffrey Chartier accompanied engineer William Rockefeller to his interview with National Transportation Safety Board investigators Tuesday and described the account Rockefeller gave.
Rockefeller, 46, had an experience almost like road fatigue or the phenomenon sometimes called highway hypnosis, Chartier said, but couldn't say how long it lasted.
When he realized he had zoned-out, he "snapped-back," but it was too late. NTSB investigators said the train was going 82 mph as it entered a 30 mph turn Sunday morning and ran off the track in the Bronx.
"You've got a good guy and an accident," he said. "A terrible accident is what it is."
What Rockefeller remembers is "operating the train, coming to a section where the track was still clear - then, all of a sudden, feeling something was wrong and hitting the brakes," Chartier said. "He felt something was not right, and he hit the brakes."
NTSB member Earl Weener said it was too soon to say whether the accident was caused by human error. Investigators have found no problems with the train's brakes or rail signals. Alcohol tests on the train's crew members were negative, and investigators were awaiting the results of drug tests, the NTSB said.
On the day of the crash, Rockefeller was on the second day of a five-day work week, reporting at 5:04 a.m. after a typical nine-hour shift the day before, Weener said. According to Chartier, Rockefeller had gotten "a proper amount of sleep," having gone to bed at 8:30 the previous night to wake up at 3:30 a.m. for his shift.
Rockefeller is currently on unpaid leave, according to the MTA. The NTSB has completed its interview with Rockefeller, and sources told WABC-TV that it left some investigators in tears over Rockefeller's profound grief for the families of the victims.
Rockefeller has worked for the railroad for 15 years and has been an engineer for 10, Weener said.
Meanwhile, Joseph Szabo, head of the Federal Railroad Administration, said in a letter Tuesday that his administration and the U.S. Transportation Department "have serious concerns" following Sunday's accident and three others that occurred in New York and Connecticut from May through July.
Szabo noted that a federal team has been working closely with Metro-North Railroad and the Metropolitan Transportation Authority, but said "immediate corrective action is imperative."
WABC-TV and The Associated Press contributed to this report.